In, for example, Swedish Patent 109,121 a book-end is proposed wherein the fixation to the shelf takes place by sliding two elements relatively to each other. A support part and the part engaging the underside of the shelf are made as a unit, with a wedge action arising by the lower part of the support being provided with a wedge track which is inclined towards the shelf. The book-end is comparatively complicated, as a track has to be made both in the fixed and in the sliding part. Moreover the adaption of the book-end to various shelf thicknesses is limited due to the wedge-track rendering no alternative variations.